1. Field of the Invention
The present invention relates to a steering nozzle angle adjusting mechanism for a jet propulsion watercraft wherein a steering nozzle is provided in addition to a jet nozzle at the stem and the steering nozzle is swung to the left and right by use of an operational cable.
2. Description of Background Art
A jet propulsion watercraft is disclosed in Japanese Patent Laid-open No. Hei 9-48394 xe2x80x9cPropulsion Nozzle Driving Device and Input/Output Conversion Mechanism for Small Watercraft Devicexe2x80x9d. A part of FIG. 1 shown in the publication is illustrated in the following FIGS. 9 and 10. The numerals set forth in FIGS. 9 and 10 have been changed for the purpose of the present description.
FIG. 9 is a side view of a propulsion nozzle provided in a conventional jet propulsion watercraft. The jet propulsion watercraft 100 comprises a jet propeller 101 at the stem, and a propulsion nozzle 102 provided on the rear side of the jet propeller 101 so as to be vertically swingable on left and right support shafts 103, 103. By driving the jet propeller 101, water is jetted from an outlet 102a of the propulsion nozzle 102, and the jet propulsion watercraft 100 is propelled by utilizing the jet force of water.
An operational cable 105 is connected to the propulsion nozzle 102 through a joint 104, whereby the direction of the propulsion nozzle 102 can be vertically changed by the operational cable 105.
Thus, by changing the direction of the propulsion nozzle 102, the posture of the watercraft body of the jet propulsion watercraft 100 can be maintained favorably according to the propulsion conditions.
Here, the joint 104 for connecting the operational cable 105 to the propulsion nozzle 102 generally has a construction in which a spherical body 106a of a fitting rod 106 is rotatably fitted to a head portion 104a, and a neck portion 104b is provided with a female screw (not shown).
In connecting the operational cable 105 to the propulsion nozzle 102 by use of the joint 104, first, a male screw provided at the rear end of the operational cable 105 is coupled to the female screw of the neck portion 104b. At this time, the protrusion amount of the joint 105 relative to the operational cable 105 is adjusted to be appropriate.
Next, the fitting rod 106 fitted to the head portion 104a through the spherical body 106a is inserted into a through-hole in the propulsion nozzle 102, and the tip end of the fitting rod 106 projects to the inner circumferential side of the propulsion nozzle 102. Subsequently, a nut 107 is screw-connected to the tip end of the fitting rod 106 thus projected, so as to fix the fitting rod 106 to the propulsion nozzle 102, thereby connecting the operational cable 105 to the propulsion nozzle 102.
After the operational cable 105 is connected to the propulsion nozzle 102, it is determined whether or not the propulsion nozzle 102 is fitted at a normal angle. When the propulsion nozzle 102 is not directed in a normal direction, the nut 107 is disengaged from the fitting rod 106, and the joint 104 is detached from the propulsion nozzle 102.
Subsequently, the joint 104 detached from the propulsion nozzle 102 is rotated relative to the operational cable 105, whereby the amount of projection of the joint 104 relative to the operational cable 105 is readjusted.
After the readjustment is completed, the fitting rod 106 is again inserted into the through-hole in the propulsion nozzle 102, and the nut 107 is screw-connected to the tip end of the fitting rod 106 projecting to the inner circumference side of the propulsion nozzle 102, whereby the fitting rod 106 is again fixed to the propulsion nozzle 102.
In this condition, it is again checked whether or not the propulsion nozzle 102 is fitted at the normal angle. When the propulsion nozzle 102 is fitted at the normal angle, the operational of connecting the operational cable 105 to the propulsion nozzle 102 is completed.
Thus, in order to readjust the angle of the propulsion nozzle 102 to a normal condition after connection of the operational cable 105 to the propulsion nozzle 102, it is necessary to disengage from the fitting rod 106 the nut 107 which has once been screw-connected to the fitting rod 106. Therefore, the operational of adjusting the direction of the propulsion nozzle 102 to the normal angle requires much labor.
FIG. 10 is a side view showing another joint for connecting a cable to a conventional propulsion nozzle. According to the joint 110, a fitting bolt 111 is inserted into a through-hole in a head portion 110a, and the tip end 111a of the fitting bolt 111 inserted in the through-hole is screw-connected to a propulsion nozzle 113, whereby an operational cable 105 can be connected to the propulsion nozzle 113.
Also in the case of using the joint 110, in order to readjust the direction of the propulsion nozzle 113 to a normal position after connection of the operational cable 105 to the propulsion nozzle 113, it is necessary to disengage from the propulsion nozzle 113 the fitting bolt 111 which has once been screw-connected to the propulsion nozzle 113.
Therefore, the operation of adjusting the direction of the propulsion nozzle 113 to the normal angle requires much labor, in the same manner as in the case of FIG. 9.
While examples of swinging the propulsion nozzle 102, 113 vertically have been described in the cases of FIGS. 9 and 10, some jet propulsion watercrafts adopt the system in which the propulsion nozzle is fitted swingably in left-right directions and the watercraft body is turned to the left and right by changing the direction of the propulsion nozzle (hereinafter referred to as xe2x80x9csteering nozzlexe2x80x9d) to the left and right directions by an operational cable.
Also in the case of connecting the operational cable to the steering nozzle, the same inconvenience as that described referring to FIGS. 9 and 10 is experienced.
Accordingly, it is an object of the present invention to provide a steering nozzle angle adjusting mechanism for a jet propulsion watercraft wherein an adjustment of the angle of the steering nozzle can be easily carried out without requiring much labor.
In order to solve the above-mentioned problems, the present invention is directed to a propulsion watercraft wherein a jet nozzle for jetting water is provided at the stern, a steering nozzle is provided in addition to the jet nozzle, and the steering nozzle is swung to the left and right by use of an operational cable to change the direction of a jet from the jet nozzle for steering the watercraft. A fitting rod is fitted to the steering nozzle side with a joint turnably supported on the fitting rod so that the joint can be fitted to and detached from the fitting rod. The operational cable can be connected to the joint and the cable length at the time when the operational cable is connected to the joint can be adjusted.
The fitting rod is fitted to the steering nozzle side, and the joint can be turnably supported on the fitting rod so that the joint can be fitted to and detached from the fitting rod, whereby the operational cable can be tentatively fixed to the steering nozzle by only fitting the joint to the fitting rod. In this way, with the condition where the joint is tentatively fixed by only fitting to the fitting rod, it can be determined and checked whether or not the angle of the steering nozzle is normal.
Therefore, even in the case where it is necessary to readjust the angle of the steering nozzle, the joint can be easily detached from the fitting rod.
The present invention includes a jet propulsion watercraft of the system in which a jet nozzle for jetting water is provided at the stern, a steering nozzle is provided additionally to the jet nozzle, and the steering nozzle is swung to the left and right by use of an operational cable to change the direction of a jet from the jet nozzle for thereby steering. The jet nozzle and the steering nozzle are each provided with positioning projections or positioning recesses for the steering nozzle on both sides of a support shaft for swingably supporting the steering nozzle on the jet nozzle.
Prior to the present invention, when the steering nozzle is mounted onto the jet nozzle, it is necessary to check whether or not the steering nozzle is disposed at a normal angle, and the check has hitherto been performed relying on the operator""s sense. Therefore, disposition of the steering nozzle at the normal angle has required skill.
In view of the above, in the present invention the jet nozzle and the steering nozzle are each provided with positioning projections or positioning recesses for the steering nozzle. By this, for example, by using the projection on the steering nozzle and the projection on the jet nozzle as marks and measuring the distance between the projections, it is possible to dispose the steering nozzle at the normal angle without requiring a great deal of skill.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.